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Cylinder to head interface.

Heads are off for rebuild, I have measured all the cylinders and they within spec for round and taper so good enough to reuse. But the top surface of the cylinder where it meets the heads has significant scuffing wear with some of the surface eroded.







Can I simply recut this surface on a lathe?
David

Old 07-21-2020, 01:37 PM
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Last edited by reclino; 07-21-2020 at 02:07 PM..
Old 07-21-2020, 01:51 PM
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Seems that all the pitting is on the outer edge of the exhaust side. The inner sealing surface seems smooth enough to lap into the heads.
Old 07-21-2020, 02:09 PM
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The cylinders have a sealing taper on the lip so be careful not to lap the taper off.
Bruce
Old 07-21-2020, 02:17 PM
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Turbo heads? Did they have taper instead of CE rings?
Old 07-21-2020, 06:30 PM
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1986 turbo heads.
Yes these have a taper surface interface.
Old 07-22-2020, 01:21 AM
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Walt, the 84 and later doesn’t us a ce ring but a taper cylinder and torque on the heads
Bruce
Old 07-22-2020, 03:01 AM
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Is it recommend to recut this taper? Or attempt to lap fit them to the heads?
Another question on cylinders regarding surface finish of a cylinder with 68,000 miles on it, I seem to remember the general wisdom here was to clean the cylinder ID with soapy water and a scotchbrite pad, but not to send the cylinders out to be honed. I can check the surface finish with a profilometer, it feels very very smooth much better than 16 rms.
Old 07-22-2020, 03:33 AM
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I have cut those before, just be real careful not to get into the plating!
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Old 07-22-2020, 08:09 AM
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Craig, you have my heads that were married up to these cylinders. The previous shop bead blasting these heads, and combustion chamber, there were matching scuff marks on the sealing surface much more visible before the bead blast.
David

Last edited by reclino; 07-22-2020 at 09:56 AM..
Old 07-22-2020, 09:00 AM
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Ill be on them this weekend, see how true the surface is and let you know..
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Old 07-22-2020, 09:04 AM
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If you have to cut them then you can use base gaskets to add it back. Host sells.

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Old 07-25-2020, 07:57 PM
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When did the Turbo cylinders go back to full fins?
Old 07-28-2020, 04:36 PM
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Did a quick check of surface finish of these cylinders. The area at the bottom not worn by the rings in microinch Ra measures 6. The area worn by the rings measures 4 Ra. This is after scrubbing the bore with hot soapy water and a fine scotchbrite pad. So will a new set of Total Seal rings bed in on this?


Last edited by reclino; 07-29-2020 at 02:09 AM..
Old 07-28-2020, 04:41 PM
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